Methods for depositing a measured amount of a species in a sealed cavity

1. A method, comprising:

depositing a microcapsule in a cavity of a semiconductor substrate, wherein the microcapsule contains an amount of a fluid;

sealing the cavity after the microcapsule is deposited; and

rupturing, after the cavity is sealed, the microcapsule to release molecules of the fluid into the cavity.

2. The method of claim 1 , further comprising setting, prior to the sealing, pressure in the cavity to be less than a desired pressure in the cavity after the rupturing.

3. The method of claim 1 , wherein the rupturing comprises heating the microcapsule to a temperature greater than a temperature applied to seal the cavity to degrade an outer shell of the microcapsule.

4. The method of claim 1 , wherein the rupturing comprises exposing the microcapsule to ultraviolet radiation, infrared radiation, or laser light to degrade an outer shell of the microcapsule.

5. The method of claim 1 , further comprising propelling a first amount of the fluid into an encapsulating fluid to form the microcapsule.

6. The method of claim 1 , further comprising:

depositing a second microcapsule in the cavity, wherein the second microcapsule contains an amount of a second fluid;

rupturing, after the cavity is sealed, the second microcapsule to release the second fluid into the cavity;

wherein molecules of the first fluid and the second fluid react to form molecules of a third fluid.

7. The method of claim 6 , further comprising applying heat, ultraviolet radiation, infrared radiation, or laser light to the molecules of the first fluid and the molecules of the second fluid to initiate a reaction that forms the molecules of the third fluid.

8. A method, comprising:

forming a cavity semiconductor in a substrate material;

depositing a film on a surface of the cavity;

sealing the cavity after the film is deposited; and

decomposing the film to form molecules of a vapor in the sealed cavity.

9. The method of claim 8 , further comprising setting, prior to the sealing, pressure in the cavity to be less than a desired pressure in the cavity after the decomposing.

10. The method of claim 8 , wherein the decomposing comprises heating the film to a temperature greater than a temperature applied to seal the cavity.

11. The method of claim 8 , wherein the decomposing comprises exposing the film to ultraviolet radiation.

12. The method of claim 8 , wherein the film comprises aluminum hydroxide or an organic compound.

13. The method of claim 8 , wherein the vapor comprises dipolar molecules.

14. A method comprising:

forming a cavity semiconductor in a substrate material;

depositing a getter material on a surface of the cavity;

exposing the getter material to molecules of a vapor, wherein the getter material adsorbs the molecules;

evacuating the vapor from the cavity;

sealing the cavity after the vapor is evacuated from the cavity; and

releasing the molecules from the getter material to provide molecules of the vapor in the sealed cavity.

15. The method of claim 14 , further comprising setting, prior to the sealing, pressure in the cavity to be less than a desired pressure in the cavity after the releasing.

16. The method of claim 14 , wherein the releasing comprises heating the getter material to a temperature that is greater than a temperature applied to seal the cavity.

17. The method of claim 14 , wherein the releasing comprises applying optical energy or electrical energy to the getter material.

18. The method of claim 14 , further comprising, after releasing the molecules from the getter material, activating the getter material to adsorb molecules of the vapor.

19. The method of claim 14 , wherein the molecules are dipolar.

20. The method of claim 14 , wherein the cavity is a waveguide of a millimeter wave atomic clock.